Steps to reproduce:
1. Host with template: Template App Zabbix Server, Template OS Linux (Template App Zabbix Agent)
2. Queries like:
SQL (0.003269): (SELECT * FROM history h WHERE h.itemid='23252' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23253' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23254' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23255' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23256' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23257' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23258' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23259' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23260' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23261' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23262' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23263' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23264' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23265' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23266' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23267' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23268' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23269' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23270' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23273' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23274' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23275' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23276' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23296' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23301' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23310' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23328' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23620' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history h WHERE h.itemid='23635' ORDER BY h.clock DESC LIMIT 2 OFFSET 0)
hosts.php:572 ? CAPIObject->delete() ? CAPIObject->__call() ? czbxrpc::call() ? czbxrpc::callAPI() ? call_user_func() ? CHost->delete() ? CItem->delete() ? CTrigger->get() ? CTrigger->addRelatedObjects() ? CItem->get() ? CItem->addRelatedObjects() ? CHistoryManager->getLast() ? DBunion() ? DBselect() in /var/www/zabbix/2.2/include/db.inc.php:525

SQL (0.000574): (SELECT * FROM history_uint h WHERE h.itemid='23271' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23287' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23289' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23290' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23291' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23292' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23313' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23315' ORDER BY h.clock DESC LIMIT 2 OFFSET 0) UNION ALL (SELECT * FROM history_uint h WHERE h.itemid='23316' ORDER BY h.clock DESC LIMIT 2 OFFSET 0)
hosts.php:572 ? CAPIObject->delete() ? CAPIObject->__call() ? czbxrpc::call() ? czbxrpc::callAPI() ? call_user_func() ? CHost->delete() ? CItem->delete() ? CTrigger->get() ? CTrigger->addRelatedObjects() ? CItem->get() ? CItem->addRelatedObjects() ? CHistoryManager->getLast() ? DBunion() ? DBselect() in /var/www/zabbix/2.2/include/db.inc.php:525